Novak Djokovic's father says his son is being kept in prison while he awaits his court hearing in Australia on Monday. 

The 20-time Grand Slam Champion had his visa revoked by the Australian Government on Wednesday for failing to meet their Covid-19 vaccine-entry requirements.

The 34-year-old Serbian, who has refused to disclose his vaccination status, is currently being held at a hotel in Melbourne which is used for mandatory quarantine for people entering the country.

His father, Srđan Đoković, says what's happened to him is unfair and that he has been set up by Australian authorities.

"Novak and his team filed the same type of documents as those 25 other tennis players and they didn't have any problems, just Novak.

"They wanted to humiliate him, they could have said 'don't come Novak' and that would have been ok, but no, they wanted to humiliate him and they're still keeping him in prison."

'He's not in detention, he's in prison'.

Novak Djokovic's father, Srdjan, says the Australian government have 'humiliated' his son and kept him imprisoned, with 'all his stuff being taken, including his wallet'.https://t.co/ETQIo3XBNB

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Concern has also been raised by Djokovic supporters about the conditions in which he is being kept.

Reigning champion Djokovic is on the verge of being deported and has a tough weekend ahead of him before he learns his fate.

The hotel is located in an inner-city suburb of Melbourne and since December 2020 has housed more than two dozen government detainees while they aim to secure a visa to stay in Australia.

Activists have held protests outside the hotel and messages have been written on the facility's walls in support of the detainees.

Previous guests have complained about their food containing maggots and mould.

Djokovic's father feels his son deserves better and has issued a rallying call for support of him.

"He's not in detention, he's in prison.

"They took all of his stuff, even his wallet, they left him with just a phone and no change of clothes, nowhere to wash his face.

"He's in prison, our pride is a prisoner of these idiots.

"Shame on them, the whole free world, together with Serbia, should rise.

"This isn't a battle for Serbia and Novak, it's a battle for seven or something billion people, for freedom of expression, free speech, freedom of behaviour.

"Novak didn't break any laws, just as seven billion people didn't break any laws.

"They want to subdue us and for us all on our knees - it won't fly, freedom Novak, we're all with you."